Self-calibration is a cost-effective method of achieving high-accuracy systems using low-accuracy components. In most systems, DC-coupled feedback paths are used to ensure greatest accuracy. However, DC-coupled feedback circuitry must deliver accuracy equal to or higher than that expected of the entire system. This requisite accuracy of feedback components dramatically increases cost, sometimes even above that of the remainder of the system.
A need therefore exists of a feedback method and apparatus for self-calibration wherein low-cost components are suitable for feedback circuitry as well.